raid one stops ubuntu from booting

[stuckeyneila1982]

/etc/mdadm/.conf
DEVICE partitions
ARRAY /dev/md/0 metadata=1.2 name=server:0 UUID=3cd07e7d:b053a4b4:802f3a05:a94b51a4

[SaturnusDJ]

/etc/fstab and /etc/mdadm/mdadm.conf aren't commands but files. You need to tell linux what you want to do with them.

cat /etc/fstab

This will print the file in terminal

nano /etc/mdadm/mdadm.conf

To edit in terminal using nano. (Another cli editor is 'vi', gedit is common for Ubuntu gui, but because your are using Lubuntu I think you need to use Leafpad.)

[darkod]

ok first error " an error occurred while mounting /mnt/5b187bea-oedd-4a92-b535-0839f6bfcdf1 press "s" to skip or "m" for manual recovery

2nd error "disk not found /mnt90c42f75-1cb3 - 4f54-97f3-2a427-4b98566 is not ready or not present

if i hit skip both it loads Ubuntu and i see a working RAID1

The first UUID is from md0. I don't know why it throws an error, maybe it's not assembled yet when it tries to boot it.

That second UUID really doesn't exist, you can see that in the blkid results. Did you have a swap on mdadm device too and somehow it got deleted? I am asking because sda2 and sdb2 have same UUID which is only possible if they were in mdadm, but there is no other mdadm device right now except md0.

[stuckeyneila1982]

Interesting. I think a long time ago i tried making a raid in ubuntu on these disks is it possible there is an extra partition or swap or some kind of object pointing ubuntu to a raid that doesnt exist? Would it be best just to delete and start over?

this is the guide i used
http://www.ducea.com/2009/03/08/mdadm-cheat-sheet/

the only other thing i did was dpkg-reconfigure mdadm
and that asked for booting with degraded setting up email notification etc.

[darkod]

It doesn't exist?

The /proc/mdstat clearly shows there is mdadm array md0 and it's assembled. Whether you are using it on purpose or not, that's not up to the computer to decide. It's only a machine.

So, do you want to break the SW raid? What will you boot? Do you have ubuntu on sdc1?

If you are not sure of anything, install and run boot-repair and create the bootinfo summary. Post the link it gives you so we can see more details.
https://help.ubuntu.com/community/Boot-Repair

[stuckeyneila1982]

neil@server:~$ sudo blkid
[sudo] password for neil:
/dev/sda1: UUID="3cd07e7d-b053-a4b4-802f-3a05a94b51a4" UUID_SUB="e0fd9083-1ace-03dc-13e2-7ee9136feae9" LABEL="server:0" TYPE="linux_raid_member"
/dev/sda5: UUID="2e0b411d-2610-46ba-8c3f-b8d8d1ca4eff" TYPE="swap"
/dev/sdb1: UUID="3cd07e7d-b053-a4b4-802f-3a05a94b51a4" UUID_SUB="db895183-94e2-5b0c-c8a2-824c58673c27" LABEL="server:0" TYPE="linux_raid_member"
/dev/sdb5: UUID="2e0b411d-2610-46ba-8c3f-b8d8d1ca4eff" TYPE="swap"
/dev/sdc1: UUID="0103df44-2e31-4dbc-a1ce-b531d2e85209" TYPE="ext4"
/dev/sdc5: UUID="6598f0b3-04a3-4f9a-bb01-7eb1de475c4f" TYPE="swap"
/dev/md0: LABEL="Raid" UUID="5b187bea-0edd-4a92-b535-0839f6bfcdfd" TYPE="ext4"
neil@server:~$

I have ubuntu on its own 500Gb drive non raid ext4 i think its sdc5 right? not sure. But ubuntu is on its own drive non raid. the RAID does not have the OS on it.

So yeah we can wipe it delete whatever. Nothing stored there.

[darkod]

To be precise, in that case ubuntu is on sdc1, the ext4 partition. sdc5 is a swap partition.

If you DO want to destroy the raid meta data, you can zero the superblock on each partition and that will delete the mdadm info. Also, open /etc/mdadm/mdadm.conf and remove the ARRAY definition.

After you have removed the definition stop the array and zero the superblock:

sudo mdadm --stop /dev/md0
sudo --zero-superblock /dev/sda1
sudo --zero-superblock /dev/sda5
sudo --zero-superblock /dev/sdb1
sudo --zero-superblock /dev/sdb5

After that it should not assemble any more.

You can reformat and reuse the sda and sdb disks as you wish.

[stuckeyneila1982]

Ok i will try after work. After i zero out the devices is the guide i used earlier in my post not correct? Could you possibly show me the commands to make a Raid1 with mdadm?

[stuckeyneila1982]

By the way darkod i really appreciate all your help.

[darkod]

Ok i will try after work. After i zero out the devices is the guide i used earlier in my post not correct? Could you possibly show me the commands to make a Raid1 with mdadm?

Assuming you want to make it from sda1 and sdb1, you only need to do:

sudo mdadm --create /dev/md0 --level=1 --raid-devices=2 /dev/sda1 /dev/sdb1

That doesn't add it automatically to mdadm.conf but you can do it with:

sudo mdadm --examine --scan >> /etc/mdadm/mdadm.conf

The ARRAY definition in mdadm.conf will assemble it on every boot.